freebsd-dev/sys/boot/pc98/libpc98/time.c
KATO Takenori dccbc08d92 PC98 version of new boot loader. Because boot2 has not yet ported,
files in boot2 directory are copies from legacy biosboot.

Submitted by:	IMAI Takeshi <take-i@ceres.dti.ne.jp>
1999-02-03 08:39:09 +00:00

84 lines
1.6 KiB
C

/*
* mjs copyright
*/
#include <stand.h>
#include <btxv86.h>
#ifdef PC98
#include <machine/cpufunc.h>
#endif
/*
* Return the time in seconds since the beginning of the day.
*
* If we pass midnight, don't wrap back to 0.
*
* XXX uses undocumented BCD support from libstand.
*/
time_t
time(time_t *t)
{
static time_t lasttime, now;
int hr, min, sec;
#ifdef PC98
unsigned char bios_time[6];
#endif
v86.ctl = 0;
#ifdef PC98
v86.addr = 0x1c; /* int 0x1c, function 0 */
v86.eax = 0x0000;
v86.es = VTOPSEG(bios_time);
v86.ebx = VTOPOFF(bios_time);
#else
v86.addr = 0x1a; /* int 0x1a, function 2 */
v86.eax = 0x0200;
#endif
v86int();
#ifdef PC98
hr = bcd2bin(bios_time[3]);
min = bcd2bin(bios_time[4]);
sec = bcd2bin(bios_time[5]);
#else
hr = bcd2bin((v86.ecx & 0xff00) >> 8); /* hour in %ch */
min = bcd2bin(v86.ecx & 0xff); /* minute in %cl */
sec = bcd2bin((v86.edx & 0xff00) >> 8); /* second in %dh */
#endif
now = hr * 3600 + min * 60 + sec;
if (now < lasttime)
now += 24 * 3600;
lasttime = now;
if (t != NULL)
*t = now;
return(now);
}
/*
* Use the BIOS Wait function to pause for (period) microseconds.
*
* Resolution of this function is variable, but typically around
* 1ms.
*/
void
delay(int period)
{
#ifdef PC98
int i;
period = (period + 500) / 1000;
for( ; period != 0 ; period--)
for(i=800;i != 0; i--)
outb(0x5f,0); /* wait 600ns */
#else
v86.ctl = 0;
v86.addr = 0x15; /* int 0x15, function 0x86 */
v86.eax = 0x8600;
v86.ecx = period >> 16;
v86.edx = period & 0xffff;
v86int();
#endif
}